The potential of Sumatran coffee agroforestry systems for conserving birds
The role of coffee based agroforestry systems as habitat for birds has been extensively studied in Latin America, but in spite of widespread deforestation, this topic has been little addressed in the rest of the tropical world, including the Asia-Pacific region. This is a study of bird assemblages in the largely deforested coffee growing landscape of Lampung Province, in Sumatra, Indonesia. It explores the potential for coffee gardens to provide adequate habitat for local forest adapted bird species. Birds were surveyed over wet and dry seasons in a range of coffee habitats; from monocultures to those with diverse tree canopies, as well as in forest and other habitat types present in the landscape. These included mature resin-producing damar agroforests which are a possible model for long term development of coffee systems. Vegetation maps and structural surveys of the bird survey plots allowed interpretation of bird records by guilds, feeding groups, bird activities and use of microhabitats, as well as taxonomically. There were clear differences in bird diversity and assemblage uniqueness between types of coffee gardens with ‘multistrata’ agroforestry systems contributing greatest to regional species richness. Nevertheless, all coffee garden types had lower diversity of birds than did forest. Frugivores and birds of high conservation dependence, were poorly represented in coffee gardens. Microhabitat use by birds was significantly different between habitats and it appeared that the birds did make use of structural features as they became available. The potential for coffee gardens in Lampung to support bird assemblages seems much lower than that in Latin America. As agroforestry development of individual coffee gardens in this region is limited in its support of threatened forest species, priority should be given to protecting forest remnants and possibly buffering these using coffee gardens that incorporate indigenous tree species in structurally and floristically diverse canopies.